Wildfire, Forests, and Climate Change
In the southwest of North America, record heat has spawned an early an aggressive start to the 2016 fire season. One consequence of a warming world is the increased frequency and intensity of wildfires. With increasing heat, fires burn more intensely over a steadily increasing wildfire season signaling a regime shift in global forests. A 2015 study published in the journal Nature Communications indicates that burn season has increased 20 percent from 1970 to 2013. In the U.S. fire seasons are now 78 days longer than in 1970.
It’s easy to count off recent record-breaking fires that confirm this trend: the Fort McMurray fire in Alberta, Canada; the Butte and Lake fires in northern California; the Okanogan fire “complex” in Washington, the largest to date in the state’s history. In Australia, a string of bushfires are among the costliest and most deadly the nation has ever seen. The list goes on...
Exacerbated by forest mismanagement, the impact of climate change on forest health has far-reaching implications on the future health of global forests. These impacts are interrelated and often self-reinforcing. Pine beetle infestation, aided by warmer winters in the western mountains of North America, is devastating many forests, making them more vulnerable to fire. Seasonal shifts and changing rainfall patterns increase the probability of wildfire. Changing habitats invite the spread of invasive species, force native species migration, and upset ecosystem balance.
Large wildfires are, of course, not new. They are a part of nature. But with human intervention, first through deforestation and mismanagement, and then from accelerating climate change, that natural balance becomes increasingly skewed. A healthy planet depends on healthy forests, so when they do burn, they regenerate and thrive. The intensity and frequency of wildfire we now see are not part of that natural cycle, but a sign that our forests are in trouble